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SBS STINGRAY Mk.I Jet Boat (LEGACY)

SeaBoss Systems (SBS) STINGRAY Mk.I Jet Boat
LEGACY: No further updates planned

Twin Jet Turbine Speed Boat with Front and Rear Control Planes in order to keep the Engines in the water... and the boat from flipping. Opted out of using the original plan to have deployable underwater fins as I found I had more control with control planes out of water.

Small Electric Drive Motors are also available but only for slow speed maneuvering (parking and taxing) and reversing. Primary power is provided by the two Jet Turbines.

Custom Tanks located in forward "mandibles" (+5k capacity Jet Fuel per side, lots of fuel).

The Air Intakes are in a protected sealed engine compartment with one way vents to take in air. The Jet Intakes don't appear to spin but I'm getting good air flow and the Jets are protected from water damage even when I have unintentially engaged "jet sub mode". When underwater the jets are still working as they appear to be using the air from the engine compartment. The only damage situations for the jet engines would either come from an accident where the Engine Compartment door was left open and water entered the compartment or the Combustion Pressure went critical (+100k). At that point the engines may be pooched and will show scratches on the Intake

CONTROLS:
Separate Throttles for:
- Port Jet Combustion (0 to 1)
- SB Jet Combustion (0 to 1)
- Jet Drive Clutch Pressure (0 to 1)
- Electric Drive Throttle (-0.4 to 1)

From Pilot Seat:
W/S - Adjust Control Plane Angle. The Control Plane Setting will display on a Numbers Readout Display in the Pilot's view on the left.
A/D - Steering LEFT/RIGHT
1 - Increase Combustion Throttle for Port and SB Jet Engines simulataneously
2 - Decrease Combustion Throttle for Port and SB Jet Engines simulataneously
3 - Increase Jet Drive Propeller Clutch Pressure
4 - Decrease Jet Drive Propeller Clutch Pressure
5 - Engage Autopilot (Steering only, there are no throttle controls for Autopilot)
6 - Change Gears (next gear ratio is 1:2, I use the next gear for slowing down when approach the destination. It's a quick way to transition from High Speed to Taxing and Parking (Local). After you go Local you can then have more time to adjust which may include shutting down the jets completely and going to Electric Drive which allows for reverse.

Autopilot available based on Tajin's model. Plug coordinates in to system using Keyboard at Navigator's station. Engage Autopilot either through clicking button at Navigator's station or hitting 5 while seated in Pilot's seat. Autopilot is for steering only. Due to the complexities for throttle adjustments for both Combustion Pressure and Drive Pressure it became to cumbersome to automate. May consider in the future. There are Displays at the Navigator's station which will show Distance to GPS Target and Bearing to GPS Target.

Craft is capable of sustained speeds with relatively calm water of 50-60 m/s. As the water gets more choppy try ajusting the control plans up. There are Two Jet Turbine Engines. One Jet powers the outer props while the other the inner props. Therefore it is technically possible to run on one engine only as the torque will still be equally split up the centre line of the ship.

Process for lighting the engines:
- Adjust Combustion Throttle for Port and/or SB Engine to at least 20%
- Turn the keys relating to th the Port and SB Fuel feeds in order to provide power to the fuel pumps and open the Jet Fuel Valves. The keys will also unlock the Compressor Buttons.
- Engage the two Compressors (Port and SB) to start pumping air in to the engines.
- Push on the Electric Motor Power Assist button to provide some RPS assistance to the turbines in order to get the Jet Engines to turn over quicker.
- Watch for Combustion Pressure alerts for both Engines (+80k). If you get alerts dial back the Combustion Throttle to reduce pressure or put load on system by engaging Jet Drive Clutch Pressure Throttle (apply slowlly as dialing the Clutch up quickly could cause too much torque which will flip your boat)

Optimum Settings for Smooth Water Operation:
38% on Port and SB Jet Combustion Chamber Throttle
26% forward on Control Plane Settings
45% Jet Drive Clutch Pressure
You should be able to maintain speed between 50-55 m/s (97 - 106 knots) and steering should be very stable

Optimum Settings for Rougher Water Operation:
35% on Port and SB Jet Combustion Chamber Throttle
40% forward on Control Plane Settings
42% Jet Drive Clutch Pressure

Optimum Settings for High Speed Run:
45% on Port and SB Jet Combustion Chamber Throttle
42% forward on Control Plane Settings
50% Jet Drive Clutch Pressure
Should be able get between 55-60 m/s (106 - 116 knots) with surges to +65 m/s (126 knots). Need to watch for AoA alerts and adjust accordingly. Steering is still relatively stable but on chopper seas, depending on the wave direction, it is possible to start "dolphin'ing" (cycle of going underwater and then jumping out with each cycle getting progressively larger). To get out of that cycle cut power to jets by setting Combustion Chamber Throttle to zero, turn off the Compressors and turn off Jet Fuel Feed. Once it settles down, relit your engines and start moving again.

Alert Systems:
NOTE: There is a button on the right side behind the Pilot Seat in the Ceiling which allows you to Silence the sound of all the alarms while the appropriate indicators will still flash.

AoA (Angle of Attack) Alert: If the front end tilts more then 0.3 upwards (Tilt sensor) there will be an indicator alert in the Pilot view as well as a beep. It is a signal to try adjusting the control planes in order to keep the nose down. Optimum Control Plane settings are 26% forward on smooth water and 32% to 40% on rougher water or when Jet throttles are engaged beyond optimum.

Sonar Depth Alert: Adjustable depth setting at Navigation Stations. Defaults to 0.0. When the depth sensed below the boat breaches the alert depth an alert will be issued.

Jet Fuel Available Alert (Port and SB): When the fuel levels move below 600 units on the Port or SB jet fuel tank an alert will be issued. If Fuel Cross connects are on it calculates the available fuel as Port + SB. If Cross Connects are off the Fuel level will be compared against the volume in the separate tanks only.

Jet Combustion Pressure Alert (Port and SB): When the Pressure in the Combustion chamber is over 80k units an alert will be issued for the correspond side. Damage to the Jet Engine appears to occur at +100k. Measures to reduce pressure would be to either reduce the Throttle for the Jet Combustion or to adjust the Jet Drive Propeller Drive Clutch in order to put load on the system.

Engine Compartment Water Level Alert: If water is detected in the Engineering Compartment an alert will be issued. There are drain pump controls in the CONTROL area near the Passenger seat used to activate pumps to clear either ENGINE COMPARTMENT or CONTROL. Dials indicate the current water level.

BREAKERS: All located in CONTROL
- Reserve Battery Power Array to Power Grid
- Main Battery Power Array to Power Grid
- Generators to Power Grid
- APU to Power Grid
- Power Grid to Systems Master
- Systems Master to Primary Systems (Light, Hatches, Displays not relating to Drive, Some Sensors)
- Systems Master to Drive Systems (Jet Drive Engines and Electric Drive Engines)

APU Electical Generator available for generating Electicity using a Small Diesel Engine.

Refueling Ports on both sides of Boat. You can attach both Diesel and Jet Fuel Connectors to the same Fuel Connector. There are Fuel Filters which will send the appropriate Fuel to the right tanks.

Tow Connector located off rear of ship with Small Connector. Controls are on top of ship (external) on the SB side.

Euipment Hatch external on SB "mandible" which contains a Dive Suit.